想問黑雨英文叫甚麼？

Black rainstorm signal

This signal means:
Very heavy rain has fallen or is expected to fall generally over Hong Kong, exceeding 70 millimetres in an hour, and is likely to continue.[1]
When the BLACK signal (Chinese: 黑色暴雨警告) is issued, Hong Kong will come to a complete standstill. Schools will not dismiss students unless there is a visible risk to staying at school, and everyone is recommended to seek shelter immediately. Buses and other forms of public transport may be halted after a while to allow commuters to go home, depending on demand and the level of risk along the route. MTR services will be limited or suspended because of the risk of flooding.

https://en.wikipedia.org/wiki/Hong_Kong_rainstorm_warning_signals

Black Rain